Pile.



)- STEWART.

PILE.

APPLLCATION FILED MAY 31-1912.

1,249,850. Patented Dec; 11, 1917.

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a core, while the ground between the edges of the opening (Z in the point and the outside of the ring F is compressed outward into the surrounding earth forming the wall of the opening.

When the two forms A and B are driven together to the desired depth, the inner form B is raised and the core of earth pushed within the inner form B is of less diameter than the inside of the inner form and will not jam therein, so that when the inner form has been lifted and inverted, the core will be quickly discharged from said form.

' In Fig. 3, I have shown the plaln outer form A and the inner form B extended beyond the outer form and contracted to produce the perforated point D. The outer surface of this point compacts the earth into the side walls, while the inner portion of the point forms the shoulder for retaining the core.

While I preferably employ an apparatus using an outer and an inner form, I may, in some instances, use a single tubular form B as illustrated in Fig. 4, in which the end D is reduced and shaped to form a point having a perforation at the center less in diameter than the inner diameter of the tube so as to produce a shoulder within the tube. This form may be used in firm ground.

In Fig. 6, I have shown an outer form A and aninner form B thesaid inner form being reduced in diameter to form a shoulder b. D is a detachable perforated point, which is driven into the ground by the action of the driver upon both the inner and .outer form and remains in the ground when the forms are removed. Upon the removal of the inner form, the core which has been projected into the form is engaged by the shoulder b and removed with the inner form. I

In Fig. 7, I-have shown a modification in which the inner form consists of a collapsible tube B of canvas or other flexible material, preferably reinforced with hoops i at intervals and provided with hinged lugs n, or other means, at the lower end to retain it in position when the pile form A is driven into the ground. The lugs n extend between the end of the pile form A and the detachable head D which is notched at the upper end to allow the lugs to extend under the driving form A At the upper end of the tube 13 is a cap it, which is lifted by the core as it is projected through the opening in the point D" when the pile form has been driven to the depth desired; the form A being finally raised to release the lug a and the extended collapsible tube with the core therein resting upon the shoulder b is removed from the tubular form.A after which-the concrete is placed within the form and finally the form itself is removed. T he cap is provided with a ring or other suitable device to be engaged by the lifting mechanism for removing the collapsible tube with the core.

In the use of forms above noted, when the inner forms have been removed, it will usually be found that a small quantity of loose hard pan will be left in the bottom of the opening. I preferably take a rammer of large diameter and pound the earth so as to form a solid bottom. The concrete is then discharged into the outside form and as the amount of concrete increases the outside form is raised, leaving in the ground a pile of large diameter, which will sustain great weights.

Thus the concrete may be rammed as the outside form is withdrawn, if found desirable. In other cases, I may fill the entire outer form with concrete and then remove the outer form.

It will be understood that these large diameter piles may be reinforced to any extent desired.

In Fig. 5, I have shown a single tubular form B having both an inner and an outer shoulder at its lower end, and encircling the point directly under the external shoulder is a detachable ring F similar to the ring F in Fig. 1. This ring is of greater diameter than the tubular form so that the hole is made larger than the form and consequently the form can be driven and removed much easier than if there was no projection at the lower end.

I claim 1. The combination of an outer form and a hollow inner form, said inner form extending beyond the end of the outer form and having a large opening at its lower end communicating with the interior of the form, the said inner form having an internal shoulder near its lower end so that a core of earth passing through the opening will be held by the shoulder.

2. The combination of an outer form and an inner form, said inner form extending beyond the end of the outer form and having a large longitudinal opening therein, said inner form having an annular shoulder and an outer tapered displacing surface extending below the outer form.

3. The combination of an outer form and an inner form, said inner form extending beyond the end of the outer form and having a reduced perforated portion and an external shoulder; and a detachable ring resting against said shoulder and against the end of the outer form.

4. The combination of an outer and an inner form; means for driving both forms at the same time, the inner form extending beyond the outer form and having a driving point; a longitudinal opening in said point of a less diameter than the inner diameter of the inner form; and a shoulder at the rasse lower end of the inner form to retain the core of earth which passes into the inner form when the pile forms are driven.

5. The combination of an outer and an inner driving form, said inner form projectingbeyond the outer form and having a reduced opening therein forming a shoulder within the inner form; a loose ring surrounding the lower portion of the inner form and extending under the outer form, said ring being greater in diameter than the outer form; and means for driving both forms simultaneously.

6. lhe combination of a tubular form having a perforated point at its lower end and arranged to receive a core of earth and having an internal and external shoulder also at the lower end; and a detachable ring encircling the point of the pile below the external shoulder so that as the form is driven into the ground it will drive the ring with it but, when the form is removed, the ring will remain in the ground.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

JOHN STEWART. Witnesses:

FRANK SHUMAN, W. G. BURKHOLDER.

homes of this patent may be obtained for flve cents each, by addressing the "Commissioner of Patents. walhinzton, D. 0." 

